Patent application EP 1 064 918 describes the application, to the hair, of metallic nanoparticles suspended in a clear composition, in order to give treated hair a shiny appearance. The deposition of the nanoparticles is described as a physicochemical adsorption process which does not make it possible to obtain remanent deposits, i.e. deposits that withstand removal by shampooing.
The inventors have discovered that it is possible to increase the remanence of metallic nanoparticles at the surface of the hair and thus to maintain their cosmetic effect even after shampooing several times, by using not “naked” metallic nanoparticles, as described in EP 1 064 918, but organomodified nanoparticles, i.e. nanoparticles bearing organic groups at their surface.